Characterization of Superscript241/Superscript

Authors: Dagmara I StrumińskaParulska Bogdan Skwarzec

Publish Date: 2014/12/23

Volume: 22, Issue: 10, Pages: 7821-7832

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Abstract

The paper presents unique data of plutonium 241Pu study in seabirds from northern Eurasia permanently or temporally living at the southern Baltic Sea coast Together ten marine birds species were examined as follows three species that permanently reside at the southern Baltic four species of wintering birds and three species of migrating birds 366 samples were analyzed The obtained results indicated plutonium was nonuniformly distributed in organs and tissues of analyzed seabirds The highest 241Pu content was found in the digestion organs and feathers the lowest in muscles Also the internal radiation doses from 241Pu were evaluatedAmong radionuclides in the environment artificial radioisotopes play a significant role in the toxic effects connected with its accumulation in organisms Manmade plutonium is widespread all over the world takes part in geochemical circulation and accumulates in the food chain Aarkrog 1977 Burger et al 2007 StrumińskaParulska and Skwarzec 2012 Plutonium is by far the most important transuranic element and its isotopes generally found in the environment are 238Pu 239Pu 240Pu and 241Pu Skwarzec 1995 Donard et al 2007 Plutonium is present in the environment as a consequence of atmospheric weapon testing reprocessing of nuclear fuel eg Sellafield Cap the la Hague Mayak and accidents in nuclear facilities as the Chernobyl accident Aarkrog 1991 Skwarzec 1995 Varga and Tarjan 2008 Bisinger et al 2010 Due to the lack of stable plutonium isotopes and their long halflives plutonium is considered one of the most important radioactive elements in safety assessment of environmental radioactivity and nuclear waste management Burger et al 2007 Plutonium is a radioactive and one of the most toxic metals and it is a hazardous environmental pollutant There are two aspects to the harmful effects of plutonium including radioactivity and heavy metal poison effects Heiserman 1997 Plutonium is considered a “boneseeker” and accumulates in liver as well Mietelski et al 2008 Moreover 241Pu T 1/2 = 1435 years decays by βemission to the longlived highly radiotoxic αemitting 241Am T 1/2 = 4322 years which has health hazards even in small concentrations due to its extremely high radiotoxicity Mussalo et al 1980 Hoffmann 2002 Strumińska and Skwarzec 2006 Most of all studies on plutonium have focused on alphaemitting isotopes so far namely 238Pu 239Pu and 240Pu There are not many data available concerning the activity concentrations of βemitting 241Pu in biological samples 241Pu seems to be less important in terms of its radiotoxicity than the αemitting plutonium radionuclides 238239240Pu but is quite significant because of its substantial contribution to the whole plutonium falloutBesides the 241Pu/239+240Pu activity ratio is a fingerprint which reveals the origin of plutonium contamination For example nuclear weapon tests fallout was characterized by a 241Pu/239+240Pu activity ratio of about 12–16 for the latitudes 40–50° North in 1963 for the Chernobyl accident deposition the 241Pu/239+240Pu activity ratio was higher reaching value of around 55–90 in 1986 Perkins and Thomas 1980 Holm et al 1992 Irlweck and Wicke 1998 SalminenPaatero et al 2014 Nuclear weapongrade plutonium which was another important source of this element in the environment was characterized by a much lower 241Pu/239+240Pu activity ratio of about 05–4 Irlweck and Hrnecek 1999 Salminen and Paatero 2009 SalminenPaatero et al 2014 This is why the simultaneous determination of 241Pu and the alpha emitting radioisotopes could be a useful tool for tracing plutonium sources in the environment Corcho Alvarado et al 2011There is a huge lack of data on 241Pu distribution and accumulation in animals Most of the studies on 241Pu distribution in a large extent referred to soils and its local contamination like Palomares Spain Gasco et al 1997 and Sellafield UK Moreno et al 1998 Merino et al 2000 postChernobylaccident research in Ukraine Buzinny et al 1994 Finland Paatero and Jaakkola 1994 Ikähaimonen 2000 and Poland Mietelski et al 1999 Komosa and Piekarz 2009 and our studies referred to the Baltic Sea Strumińska and Skwarzec 2006 StrumińskaParulska and Skwarzec 2013 Our previous experiments on the air dust samples collected in 1986 over Gdynia northern Poland the year of the Chernobyl accident indicated extreme increase of 241Pu amount in the atmospheric dust in April 1986 the 241Pu activity reached 3643 Bq kg−1 dry weight dw Starting from May 1986 331 Bq kg−1 dw the 241Pu concentrations in the air dust were decreasing systematically and in November 1986 it reached the level before the Chernobyl accident 108 Bq kg−1 dw The 241Pu/239+240Pu activity ratio in the air dust samples increased from 34 March 1986 to 56 April 1986 after the accident and decreased slowly reaching 36 December 1986 Strumińska and Skwarzec 2006 Similar situations were observed in Vienna and Salzburg Austria Belgrade Serbia and Vilnius Lithuania Irlweck and Wicke 1998 Vukanac et al 2006 Lujaniene et al 2009 Mietelski et al 1999 suggested that the initial at the moment of the Chernobyl accident deposition of 241Pu in Poland might have been relatively high up to the level of 2 kBq m−2 The maximum result of 241Pu in forest soil was estimated at 254 Bq kg−1 dw and the enhanced levels of this isotope were observed in all samples from the northeastern Poland Our previous researches showed that the principal source of 241Pu on the Polish territory and the southern Baltic area was the Chernobyl accident Strumińska and Skwarzec 2006 StrumińskaParulska and Skwarzec 2012 StrumińskaParulska and Skwarzec 2013Plutonium can be accumulated in the biota and for this reason it could be an important source of radiation dose in the body of animals Skwarzec 1995 Chibowski et al 2006 Mietelski et al 2008 Birds are characterized by high body temperature and intensive metabolism what cause high daily food requirement Tomiałojć and Stawarczyk 2003 Most of them are multihabitat species and they are a significant part of the biotas Seabirds are a very important element of the trophic chain of marine ecosystem as well Particularly the birds’ feathers are often used as bioindicators of heavy metals contamination in marine and air environment Pilastro et al 1993 Burger and Gochfeld 1997 There were high differences observed in some radionuclide concentrations among migratory and sedentary birds However migratory birds as it appears cumulate more radionuclides as they operate in many diversified habitats Krumholz 1954 Krivolutsky et al 1999 Mietelski et al 2006 Burger et al 2007 Kitowski et al 2008 Mietelski et al 2008 Gaschak et al 2009 Kitowski et al 2009 Howard et al 2013 Matishov et al 1996 reported on caesium137 in seabirds in the Barents Sea but very few data on radionuclide levels in seabirds are available One might anticipate that levels in mollusceating shorebirds and seaducks could be elevated in areas such as the Cumbrian coast but this does not seem to have been investigated Tasker and Furness 2003From over 9000 species of birds in the world approximately 200 species are related to the Polish part of the Baltic coastal zone Żmudziński 1990 Tomiałojć and Stawarczyk 2003 That is why they could be one of the constituent in radionuclides transport Navarro et al 1998 Brisbin 1993 stated seabirds were probably not very useful in radionuclide monitoring because levels did not tend to increase food chains and the assimilation efficiency of most radionuclides through the digestive system of seabirds was poor However the knowledge on 241Pu distribution is indispensable for the correct assessment of its radioactive contamination and the radiological consequences Current knowledge about bioaccumulation of plutonium 241Pu in birds is still very poor In Eurasia there were no studies on 241Pu contamination in birds Krivolutsky et al 1999 Burger et al 2007 Kitowski et al 2008 Mietelski et al 2008 Gaschak et al 2009 While models are useful in predicting what concentrations might be expected in different biota compartments in ecosystems measurements of actual concentrations in biota and food consumed would be clearly more directly useful in predicting intake rates and ultimately doses Burger et al 2007The paper presents the results of 241Pu activity concentration measurements in tissues and organs of ten seabird species collected at the southern Baltic Sea coast The aim of the investigation was to assess the level of 241Pu contamination of marine birds that live in northern Eurasia indicate the main bioaccumulation organs calculate the values of bioconcentration factors BCFs and evaluate the internal radiation doses from 241Pu Moreover the present study can help to recognize the plutonium sources in marine birds link the diet and living habits to the differences in plutonium distribution and provide valuable information about plutonium transfer between atmosphere and sea

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